Field-effect controlled power switching structures such as a Metal Oxide Semiconductor Field-effect Transistors (MOSFETs) or an Insulated Gate Bipolar Transistors (IGBTs) have been used for various applications including but not limited to switches in power supplies and power converters, e.g., half-bridges.
The direction of current flow through the field-effect controlled structures operating as switches is different in different operating cycles. In an on/off-mode or forward mode of the field-effect controlled structure, a pn-body diode at a body-drain junction of the field-effect controlled structure is reversely biased and the resistance of the device can be controlled by the voltage applied to the gate electrode of the field-effect controlled device. In a diode mode of the field-effect controlled device, the pn-body diode is forward biased. This results in a loss which is mainly determined by the product of current flow and voltage drop across the body diode. The pn-body diode may be forward biased when switching inductive loads, for example.
In view of meeting the demands on electrical characteristics of field-effect controlled power switching structures, it is desirable to reduce switching losses of the pn-body diode in field-effect controlled power switching structures.